I’m in a similar setup where I live in Australia. Our house has solar and battery — unlike the people in the FA, we purchased it directly ourselves, although with a significant government rebate.
Our battery is under automatic VPP control, but it’s not like it randomly starts exporting when we don’t want it to. When regional demand is high (hot days) or supply is low (no wind or cloudy), our battery might start exporting. But that’s a good thing for us, because our electricity is priced wholesale and changes every 5 minutes, and export rates are high in this situation. A couple of times there have been price spikes and we’ve made a few hundred dollars in under a hour. It’s a win-win for us (making money) and the grid (providing stability). To be fair, those spikes are rarer now than they were a year ago.
You can always control the battery if you want. Sometimes I’ll manually export even if prices aren’t high if I know I don’t need the power in my battery. Sometimes I’ll prevent export if I know I want to charge the car overnight from the battery. But mostly I let it do its thing.
From an investment perspective, the battery has been a no-brainer. Even without the windfalls from price spikes, being able to defer grid consumption to daylight hours (when wholesale prices are very cheap or even negative, i.e. we get paid to charge the car) puts the ROI in the 3-5 year range.
Orthogonal but related: where I live, homeowners might get charged negative prices at times for solar re-injected in the network. This doesn't make a ton of sense for me since you could just unplug the panels instead of being charged for the production! However, the electric company charges you retroactively (on a 15-min bucket) so you would need an accurate model to "beat them at their game". Negative electric prices in a country with a huge amount of solar/wind/hydro is surprising, since all of these production methods can stopped on demand (and even reversed in the case of some hydro setups).
Maybe I’m not picturing it correctly but wouldn’t a negative price mean more money in your wallet? Or are you saying that the set price is less than it costs to produce the energy on your side?
This is a problem on Hawaii where the combination of an island power grid (can't sell it to the next grid over) and optimal conditions for solar.
They've added some grid scale batteries - <a href="https://www.asce.org/publications-and-news/civil-engineering-source/civil-engineering-magazine/article/2024/03/large-battery-energy-storage-system-now-operating-in-hawaii" rel="nofollow">https://www.asce.org/publications-and-news/civil-engineering...
> Situated on 8 acres of industrial land, the Kapolei Energy Storage project comprises 158 Tesla Megapack 2 XL lithium iron phosphate batteries, which are about the size of a shipping container. All told, the KES project provides 185 MW of total rated power capacity, or the largest possible instantaneous discharge, and 565 MWh of energy capacity, or the maximum amount of stored energy.
> The system can meet 17% of Oahu’s electricity demand for three hours at peak load or six hours at half load, Brandon Keefe, the executive chair of Plus Power — the company that developed the project — told USA Today. Plus Power “develops, owns, and operates standalone battery energy storage systems that provide capacity, energy, and ancillary services, enabling the rapid integration of renewable generation resources,” according to the company’s Jan. 11 news release announcing the start of operations at its KES facility.
There's also a practical.engineering episode on this: <a href="https://practical.engineering/blog/2024/3/18/how-the-hawaiian-power-grid-works" rel="nofollow">https://practical.engineering/blog/2024/3/18/how-the-hawaiia...
And today... <a href="https://www.hawaiianelectric.com/products-and-services/smart-renewable-energy-programs/previous-renewable-programs/net-energy-metering-plus-and-nem-plus-limited-export" rel="nofollow">https://www.hawaiianelectric.com/products-and-services/smart...
The amount of power rooftop solar in Hawaii is allowed to export to the grid is regulated.
> Customers enrolled in NEM Plus Limited Export are required to install a control device at the utility meter to limit the combined export capacity of the existing and additional generation to the capacity of the original NEM system. The battery must be programmed to 'load-following' mode so as not to export to the grid -- except when providing exports for grid services.
nonfamous · · focus · HN ↗
Our battery is under automatic VPP control, but it’s not like it randomly starts exporting when we don’t want it to. When regional demand is high (hot days) or supply is low (no wind or cloudy), our battery might start exporting. But that’s a good thing for us, because our electricity is priced wholesale and changes every 5 minutes, and export rates are high in this situation. A couple of times there have been price spikes and we’ve made a few hundred dollars in under a hour. It’s a win-win for us (making money) and the grid (providing stability). To be fair, those spikes are rarer now than they were a year ago.
You can always control the battery if you want. Sometimes I’ll manually export even if prices aren’t high if I know I don’t need the power in my battery. Sometimes I’ll prevent export if I know I want to charge the car overnight from the battery. But mostly I let it do its thing.
From an investment perspective, the battery has been a no-brainer. Even without the windfalls from price spikes, being able to defer grid consumption to daylight hours (when wholesale prices are very cheap or even negative, i.e. we get paid to charge the car) puts the ROI in the 3-5 year range.
amenghra · · focus · HN ↗
c0wb0yc0d3r · · focus · HN ↗
Someone · · focus · HN ↗
Conversely, at such times you can get paid to consume electricity.
shagie · · focus · HN ↗
They've added some grid scale batteries - <a href="https://www.asce.org/publications-and-news/civil-engineering-source/civil-engineering-magazine/article/2024/03/large-battery-energy-storage-system-now-operating-in-hawaii" rel="nofollow">https://www.asce.org/publications-and-news/civil-engineering...
> Situated on 8 acres of industrial land, the Kapolei Energy Storage project comprises 158 Tesla Megapack 2 XL lithium iron phosphate batteries, which are about the size of a shipping container. All told, the KES project provides 185 MW of total rated power capacity, or the largest possible instantaneous discharge, and 565 MWh of energy capacity, or the maximum amount of stored energy.
> The system can meet 17% of Oahu’s electricity demand for three hours at peak load or six hours at half load, Brandon Keefe, the executive chair of Plus Power — the company that developed the project — told USA Today. Plus Power “develops, owns, and operates standalone battery energy storage systems that provide capacity, energy, and ancillary services, enabling the rapid integration of renewable generation resources,” according to the company’s Jan. 11 news release announcing the start of operations at its KES facility.
There's also a practical.engineering episode on this: <a href="https://practical.engineering/blog/2024/3/18/how-the-hawaiian-power-grid-works" rel="nofollow">https://practical.engineering/blog/2024/3/18/how-the-hawaiia...
<a href="https://www.hawaiinewsnow.com/story/23689275/lawmakers-call-hearing-to-discuss-hecos-solar-policy-changes/" rel="nofollow">https://www.hawaiinewsnow.com/story/23689275/lawmakers-call-...
And today... <a href="https://www.hawaiianelectric.com/products-and-services/smart-renewable-energy-programs/previous-renewable-programs/net-energy-metering-plus-and-nem-plus-limited-export" rel="nofollow">https://www.hawaiianelectric.com/products-and-services/smart...
The amount of power rooftop solar in Hawaii is allowed to export to the grid is regulated.
> Customers enrolled in NEM Plus Limited Export are required to install a control device at the utility meter to limit the combined export capacity of the existing and additional generation to the capacity of the original NEM system. The battery must be programmed to 'load-following' mode so as not to export to the grid -- except when providing exports for grid services.